physics problem! 物理问题. 请帮助!!

这些问题我用英文的方式写下.. 要是你明白的话又会做的话请近来帮忙.. 记得show your works.

1. A 3.08 kg block slides down a frictionless plane inclined 19.7° to the horizontal. If the length of the plane's surface is 1.53 m, how much work is done, and by what force?
2. A student has six textbooks, each with a thickness of 4.0 cm and a weight of 38 N. What is the minimum work the student would have to do to place all the books in a single vertical stack, starting with all the books on the surface of the table?

1 做功的是重力，所做功的大小为3.08*9.8*1.53*sin19.7°≈15.57

2 6*38*0.12-6*38*0.02=22.8